Abstract
Background and aim
Multiple interventions and policy changes related to opioid agonist treatment (OAT) have been introduced in British Columbia, Canada to increase engagement and retention in OAT. We aimed to estimate the impact of policy changes and the announcement of the opioid overdose-related public health emergency on the use of OAT for incarcerated individuals with opioid use disorder.
Design
Interrupted time series analysis. Events of interest included the expansion of buprenorphine/naloxone into provincial health care insurance coverage in October 2015 and the public health emergency declared in April 2016.
Setting and participants
Our study included 9,220 incarcerated individuals from 12 provincial corrections facilities in British Columbia, Canada for a total of 75,649 calendar-months of incarceration.
Measurements
Monthly measures of OAT use during incarceration from January 1st 2013 to September 30th 2017. We estimated changes in OAT use, controlling for individual and facility-level factors, using a general estimating equation, specified with a logit link and an autoregressive correlation matrix.
Findings
After the provincial health insurance coverage expansion, a sharp increase in OAT use during incarceration was observed (adjusted odds ratio (aOR): 1.16, 95% confidence interval (CI): (1.13, 1.19)). The public health emergency coincided with an immediate but temporary increase in OAT receipt (aOR: 1.34, 95% CI: (1.22, 1.47)). Over the entire study period, we estimated a ten-fold increase in the adjusted odds of OAT use during incarceration (aOR: 10.10, 95% CI: (8.98, 11.37)).
Conclusion
Following an expansion of healthcare insurance coverage to include buprenorphine/naloxone, receipt of opioid agonist treatment (OAT) within correctional facilities in British Columbia, Canada increased, largely driven by an increase in buprenorphine/naloxone prescriptions among individuals without recent OAT experience.